water benchmarking and best practices
TRANSCRIPT
Environmental Sustainability Advisory Group
Water Benchmarking and Analysis subgroup
Auto OEMs benchmarked Water management, use, and best
practices
FCA, Ford, GM, Honda, Nissan, Toyota participated
Identified 135 aspects to benchmark – Metrics, Management,
processes, sustainability, and best practices
Benchmarking helps identify areas for improvement with best
practices
Next steps are to extend to Automotive Supply Chain
The AIAG Water Workgroup Provides A Forum For Benchmarking and promoting water reduction activities
Environmental Sustainability Advisory Group
Water Benchmarking and Analysis subgroup
Results
Auto OEM sites
included in
Water
Benchmarking
#
Assembly 51
Engine 26
Transmission 18
Casting 12
Stamping 22
Non-
Manufacturing
facilities 20
Total 149
OEM:
Avg. 3.5
Scope is North American Automotive OEMs Only one OEM included Non-Manufacturing and it is excluded in this chart
Environmental Sustainability Advisory Group
Water Benchmarking and Analysis subgroup
Results
High – low volumes Low – high volume and water stressed
Assembly
Source
Per-cent
of total
Ground Water 13%
Surface Water 2%
Municipal 83%
Grey Water 1%
Rain Water 0%
Municipal source is most common Lowest use per vehicle is high volume or water stressed areas
OEM:
Environmental Sustainability Advisory Group
Water Benchmarking and Analysis subgroup
Results
Engine
High – low volumes Low – high volume and water stressed
OEM:
Environmental Sustainability Advisory Group
Water Benchmarking and Analysis subgroup
Results
Casting High – Aluminum, low volumes Low – Iron casting, Aluminum high volume
OEM:
Environmental Sustainability Advisory Group
Water Benchmarking and Analysis subgroup
Results
Stamping
High – low volumes Low – high volume
OEM:
Auto OEM Water Best Practices
Best Practices shared for water efficiency
Perform Site-Wide Water Balance to Better Understand Water Usage, identify opportunities and knowledge gaps
Develop Water Scorecard and integrate into Site Business Plan
Implement Aggressive Water Reduction and Recycle, up to and including ZLD in water stressed regions
Install Real-Time Water Metering for High Water Usage Area/Department
Implement Rinse System Cascading
Install Conductivity Control on Fresh Water make-up to Rinses
Use RO Reject for Cooling Tower or Paint Sludge System Make-up
Use Job Present Sensor to control Fresh Water Rinse Inputs (automatic turn off rinses during gaps in production)
Process Stage Make-Up Water Supplied from Respective Rinse Stage
Capture Cooling Coil Condensate for reuse (paint sludge system or cooling tower)
Specify 85% recovery RO systems to reduce RO Reject (75% is typical)
Track Water/Sewer Usage
“What gets measured, gets done!”
• Track Incoming Water, Revenue Meters
• Install Water Meters for High Water Usage Area/Department
“If a meter is installed and no-one reads it, Does it still measure water?”
• Measuring Water Necessary for Management Buy-In and Business Case Development
Develop Water Scorecard/Tracking
• Track Usage Monthly (at Least)
• Management Commitment to Water Reduction
• Develop Company Reduction Goal
– Normalized to Production
• Set Goals by Facility (or Department)
• Integrate into Business Plans
• Incentives
– Recognition, Friendly Competition
– Tie to Plant Manager Bonus
Perform Site-Wide Water Balance
• Better Understand Water Usage
• Identify Largest Users (and Knowledge Gaps)
• Identify Opportunities
• Develop Business Cases
• Prioritize Projects
• Present to Management
Paint Shop Water Usage
• 80% of Assembly Plant Water
• Pretreat 30-40%
• E-Coat 10-20%
• Paint Sludge 5-10%
• Humidification 5-10%
• High Purity Water 5-10% (Reject)
• Cooling Towers 10-20%
Rinse Systems – Best Practices
• Additional Rinse Stages Reduces Water • Cascade Rinses from Cleanest to Dirtiest • Job Present Sensors/Automatic Shut Off Fresh Water • Knock-Off Rinse • Contaminant Measurement/Control (Log Sheets,
Graphs, Spec) • Process Make-Up with Excess Rinse Water • Rinse Wastewater Recovery – Membrane Process,
Capacitive DI
Pretreatment (Phosphate or Thin-Film)
Clean RO or CW
Rinse Conversion
Coating RO Rinse
E-Coat Permeate
Rinses RO Rinse
E-Coat
Rinse System – 80 gpm
Clean
Spray Rinse
Spray Rinse
Dip Rinse
Final
Fresh
Rinse
F Flow Meter
Fresh Water
35 gpm
Fresh Water
5 gpm
Fresh Water
20 gpm
Fresh Water
20gpm
L Level Control – Make-Up
L
Optimized System – 17 Mg/yr Water Savings
$172,000 Water/Sewer Savings
Clean
Spray Rinse
Spray Rinse
Dip Rinse
Knock Off
Rinse 25 gpm
Final
Fresh
Rinse
F J F
J
F
J
Flow Meter
Job Present Shut Off
L
L Level Control – Make-Up
Fresh Water
30 gpm
X M/U 5 gpm
System Control Log
• Example Rinse Contamination
• Rinse 2A Spec <8 actual 1.2
• Rinse 2B Spec <4 actual 0.5
• Rinse Stg 3 Spec <2 actual 0.4
• This Log Shows Rinses are Well Below Specification – Opportunity for Water Reduction!
Reverse Osmosis
• Specify 85% vs Typical 75% Recovery
• RO Reject to Cooling Towers
• RO Reject to Paint Sludge System
• RO Reject Recovery – New Technologies
Cooling Towers
• Most Locations can run 5-6 Cycles of Concentration
• Proper Chemical Control
• Monitor for Scaling and Corrosion
• Alternate Sources of Water, eg. RO Reject
• Hardness Removal Technologies for Very High COCs
Other Opportunities
• Water Usage Unknown – Measure it! • Poor Maintenance – Things not Working • Rinse Job Present Sensors Not Installed/Working • Rinse Contamination Control – Manual, Automatic,
None • Steam Condensate Return – Energy + Water
• Improper Level Control – Overflow (water and chemicals)
• Limited or No Cascading • Frequent Tank Dumps • Leaking “Dump” Valve
Alternate Water Sources
• Require Chemical Analysis, System Knowledge
• Cooling Coil Condensate/Humidification Blowdown for Reuse (paint sludge system or cooling tower)
• Treated Industrial Wastewater to Cooling Towers
• Foundation Drainage (Artesian Well) to Cooling Towers, Paint Sludge
• Stormwater for Cooling Towers, Sludge System, and RO Feed, etc.
• Treated Industrial/Sanitary for CT, Irrigation, Toilet Flushing
• Zero Liquid Discharge